BACK IN THE BOX: Jose Reyes, an early arrival at Mets camp as he comes back from hamstring issues, takes a hack in Port St. Lucie yesterday. Photo: Anthony J. Causi / New York Post

Thinking about home runs might not be such a bad thing. After watching the Mets finish last in the major leagues with 95 homers in 2009, hitting coach Howard Johnson isn’t afraid to admit the organization needs a change in approach this season.

As easy as it seems to blame injuries and the team’s move to Citi Field last year for the Mets finishing with nearly half the homers they hit in 2008, Johnson said there were other factors at work, including an emphasis on hitting to the opposite field that began in spring training.

“As an organization, we wanted to be a good offensive team with runners in scoring position,” Johnson said as the Mets prepare to officially open camp tomorrow in Port St. Lucie.

“We wanted to be a good offensive club when it comes to strikeouts. We wanted to walk a lot and have a high on-base percentage. We achieved those goals in those areas, but we dropped in power. That is something we’re going to address this year.”

Of course, a potentially good first step was signing Jason Bay to play left field, allowing the Mets to envision 30-plus homers from a previously problematic position.

But Johnson also points to having Jeff Francoeur for a full season and the strides Daniel Murphy made in last season’s second half. At the top of the hitting coach’s list is getting David Wright back to the player who hit at least 25 homers in each of his first four full seasons. Wright hit only 10 homers last year.

Johnson indicated Wright’s biggest challenge will be mental.

“He is going to be under somewhat of a microscope this spring and those things are a factor — you can’t ignore it,” Johnson said.

“The goal for me is to keep him on a day-to-day thought process and not get ahead of himself and not try to put up numbers in spring training. That’s not the goal. The main thing is having him on track for Opening Day.”

Johnson said the addition of Bay and Jose Reyes’ return to the lineup should help Wright relax at the plate.

“As much as [Wright] had his ups and downs last year, he still hit .300, so usually guys with power, they are going to figure some things out,” Johnson said. “We have a plan in place for David and it’s going to take the spring to get him to kind of where we want him to be, but I know he looks great, he’s worked out extremely hard. I know mentally he is raring to go.”

Bay, whom the Mets signed to a four-year contract worth $66 million with a vesting option for a fifth season, has spoken at length with Johnson on the phone. Johnson said Bay conveyed to him a message of wanting to improve on last season’s .267 average with 36 homers and 119 RBIs.

“He is not satisfied with doing what he’s done,” Johnson said. “Whenever you have an athlete of that caliber and a guy who can put up those kind of numbers, on top of that the experience of going to place like Boston, that is not an easy task.

“When you put all those things together and he wants to get better, you can’t help but think that is going to be a huge impact on the rest of the group.”